#include <iostream>

using namespace std;

int main()
{
	int ntest;
	cin >> ntest;
	for (int i = 0; i < ntest; i++)
	{
		int a, b;
		cin >> a >> b;
		int sum = 0;
		for (int j = a ; j <= b; j++)
			if ((j & 1) != 0) sum += j;
		cout << "Case " << i+1 << ": " << sum << endl;
	}
	return 0;
}
